1. Field of the Invention
The present invention relates to a mount assembly for an automotive power plant, and, more particularly, to an improved mount assembly capable of preventing rocking of the power plant and also of preventing engine and transmission vibrations from being transmitted to a vehicle body so as to enhance the ride comfort of a vehicle.
2. Description of the Related Art
Typically, an automotive power plant having an engine and a transmission is mounted transversely in a vehicle. When mounting the power plant on the vehicle body, a plurality of mounts are used for preventing rocking of the power plant and preventing the engine and transmission vibrations from being transmitted to the vehicle body.
FIG. 9 shows a power plant mounted on a vehicle by employing a plurality of mounts. A power plant 104 comprises an engine 100 and transmission 102 arranged transversely in a vehicle and is fixed to the vehicle body by first, second, third, and fourth mounts 106, 108, 110, and 112. The mounts 106, 108, 110, and 112 are respectively located in four directions around the power plant. That is, the first mount 106 is positioned in the vicinity of the engine-side end of the power plant and the second mount 108 is positioned in the vicinity of the transmission-side end of the power plant. The third and the fourth mounts 110 and 112 are respectively mounted in the vicinity of power plant""s vehicle-front end and vehicle-rear end.
The first mount 106 connects the engine-side of the power plant 104 and the vehicle body by fixing one end of a mounting bracket 118 (the other end of the mounting bracket 118 being connected as shown in FIG. 10 by means of bolt to one end of an engine support bracket 114 which is fixed and supports the engine 100) and by being connected to a mounting bracket 124 fixed to the vehicle body which is supported on a front apron 122 and a side member 120 that are provided on the inner surface of the vehicle body. The first mount 106 is inserted in the mounting bracket 124 and fixed thereon by means of bolt 126 to which penetrates openings formed at the center of the first mount 106 and the mounting bracket 124 and a nut 128 (see FIG. 9).
However, since the first mount 106 is connected to the mounting bracket 124 such that the axial bore through which the bolt 126 passes is oriented along the longitudinal direction of the vehicle body, the rigidity of the mounting bracket 124 in the longitudinal direction of the vehicle is deteriorated. Accordingly, the first mount can not efficiently prevent rocking of the power plant especially when the vehicle is abruptly accelerated and it also can not prevent the engine and transmission vibrations from being transmitted to the vehicle body. This results in a deterioration of the ride comfort of the vehicle.
The present invention has been made in an effort to solve the above problems of the prior art.
It is an object of the present invention to provide a mount for an automotive power plant capable of preventing rocking of the power plant and also of preventing the engine and transmission vibrations from being transmitted to the vehicle body by effectively absorbing vibrations of the power plant so as to improve the ride comfort of the vehicle.
To achieve the above object, in a power plant mounting structure for vehicle including an engine side mount assembly, a transmission side mount assembly, and front and rear mount assemblies, the engine-side mount assembly comprises a mount which is less stiff in front and rear directions than in the upward and downward directions of the vehicle, and is arranged such that an axis of the mount is parallel to an inertial axis of a moment of inertia of the power plant. Furthermore, it also comprises a linkage member for connecting the mount to an engine-side of the power plant by coupling a screw member coaxially fixed at the center of the mount with a screw block fixed to the engine-side of the power plant, and a mounting bracket for fixing the mount to a side member of the vehicle body.